(a) Field of the invention
The present invention relates to a method for cleaning a septic tank, which method permits preservation of the bacteriological medium and causes an important reduction in the amount of waste withdrawn. The disclosure also relates to a tanker for carrying out this inventive method.
(b) Brief description of the prior art
The conventional method commonly used for cleaning septic tanks consists in completely emptying all the fermentation and decantation compartments of the septic tank by means of a pump that sucks up their content. The heavy sludges which are generally sedimented and the light sludges floating onto the surface of the bacteriological liquid medium are suck up together with the liquid medium, thereby forming a very liquid mixture once stocked in a tanker. In practice, this method necessitates reformation by sowing of a new population of septic bacteria after each cleaning, before the tank may take again its digestive work. Furthermore, this method provides large volumes of liquid waste that are source of pollution for the environment and involve considerable cost for their treatment, disposal and transport.